Investment in Kronos Worldwide, Inc. - Changes in Carrying Value of Investment (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Balance at the beginning of the period	$ 292,206
Equity in earnings of Kronos Worldwide, Inc.	(4,637)	$ 17,533
Dividends received from Kronos	(6,692)	$ (6,692)
Equity in Kronos' other comprehensive income (loss):
Balance at the end of the period	278,449
Kronos
Balance at the beginning of the period	292,200
Equity in earnings of Kronos Worldwide, Inc.	(4,600)
Dividends received from Kronos	(6,700)
Equity in Kronos' other comprehensive income (loss):
Currency translation	(2,100)
Defined benefit pension plans	100
Other	(400)
Balance at the end of the period	$ 278,500

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Amount of distribution received from equity method investee for return on investment, classified as operating activities. Excludes distribution for return of investment, classified as investing activities.

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Amount before tax, after reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount, before tax, after reclassification adjustment, of (increase) decrease in accumulated other comprehensive income for defined benefit plan.

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